NEW YORK (360Dx) – Leveraging four years of work standardizing ambulatory point-of-care laboratory testing throughout the University of California, Los Angeles Health system, UCLA's department of pathology and laboratory medicine has conducted its first patient outcome study focused on outpatient lab testing.
"We have done other outcome studies in the inpatient side," said Omai Garner, assistant clinical professor in the department of pathology and laboratory medicine, and director of point-of-care testing and interim section chief for microbiology, with UCLA Health. "This is really the first of its kind exploring ambulatory and outpatient medicine."
The study, conducted from March to September of last year at three UCLA Health urgent care clinics, evaluated whether the higher sensitivity of a BioFire rapid PCR flu testing compared to antigen flu testing would affect the amount of antibiotics that physicians prescribe, Garner said. The study enrolled approximately 100 patients and is expected to be submitted for peer review this summer.
Reaching the point of being able to conduct a patient outcome study of point-of-care testing in outpatient labs has involved four years of standardizing lab tests and testing procedures in UCLA Health's large, dispersed ambulatory care network, Garner said. UCLA has approximately 200 ambulatory labs, ranging from urgent care clinics to physician office labs spread across a 300-square-mile radius, he said. More than 100 of the ambulatory labs conduct point-of-care testing.
In terms of evaluating patient outcomes in ambulatory medicine, UCLA's extensive ambulatory network is both its best asset and its biggest challenge, according to Garner.
"Most large academic medical centers don't have this large of an ambulatory footprint," he said. "UCLA has this very large extended outpatient area, so it gave us the ability to do this type of work."
With more than 100 of the system's ambulatory labs performing point-of care testing, and approximately six or seven medical assistants performing tests at each of those ambulatory labs, the scale of UCLA Health's ambulatory network also means there are close to 1,000 people performing Clinical Laboratory Improvement Amendment-waived tests throughout the system, according to Garner. By contrast, the centralized clinical microbiology laboratory at UCLA, which Garner also oversees, has approximately 40 to 50 trained laboratorians performing all the testing.
"The challenges of 1,000 different users running all these different tests is how do you know that they are all trained appropriately, that they are all performing the test correctly, that they are all interpreting the test correctly, and how do you put the infrastructure in place to be able to do that," Garner said.
Adding to the challenge, most of the labs in the ambulatory network are specialty clinics, such as dermatology clinics, Ob/Gyn clinics, or endocrinology clinics that perform different types of testing, according to Garner. He estimated there are more than 30 primary care clinics, as well as four urgent care clinics.
Before the standardization effort began, many of the labs that performed the same type of testing used tests from different manufacturers, Garner noted.
"There are multiple manufacturers for each of the tests and all of the tests aren't as good as other tests, so they don't have the same sensitivity and specificity. One thing we tried to do was make sure everybody is using the best test available," Garner said.
While most doctors were not loyal to a particular test, Garner noted there was some pushback if a test that UCLA recommended was more expensive than a test the clinic was currently using.
"What I have to emphasize is that even if that one is cheaper, it's not as good as this other one. This other one is the one that UCLA recommends because we did a verification, so we know it's the best test," Garner said.
Once the tests that labs use was standardized, it was essential to ensure that all labs were performing quality control testing. Quality control is performed at different intervals, depending on the test, ranging from daily for some tests, to monthly for others. All ambulatory labs must keep a log of the quality controls they perform for each test. There are ambulatory nurses assigned to oversee groups of ambulatory clinics who check quality control logs as they do safely rounds, Garner noted.
Medical assistants also had to be trained to ensure that they were following testing procedures explicitly when they performed tests and read test results. That might mean that if a test result is supposed to be read in five minutes, it must be timed to a five-minute interval, rather than read when it seems like five minutes had passed, Garner said. Labs were all given timers to ensure that they were following protocols.
"You have to follow the rules precisely or it is not a CLIA-waived test anymore. Regulations state that it becomes a high complexity test if you change when you do the reading," Garner said. "That was our third step to make sure everybody was performing the test exactly as the package insert dictated."
Ambulatory labs were further inspected to ensure that lab testing areas were clean and properly organized, Garner noted.
"We look at the space where they are doing the testing and try to organize it efficiently, so people aren't walking far distances," Garner said. "A clinic is a high-traffic area, particularly when you consider something like an urgent care. We are able to minimize some of the excess work that would go into not doing things efficiently, and actually help the clinic do their business better. That is the last piece."
Some of the issues standardizing testing in an ambulatory environment were summarized in an article titled Ensuring the Quality of Point-of-Care Testing in a Large Decentralized Ambulatory Care Setting, published in the American Journal of Clinical Pathology in September 2017.
The ambulatory lab standardization effort set the stage for conducting patient outcome studies, such as the BioFire rapid PCR flu test study conducted last year, Garner said. He and coauthor Valerie Arboleda, assistant professor at the David Geffen School of Medicine at UCLA, noted the potential to use the standardized outpatient environment for patient outcome studies in the American Journal of Clinical Pathology article, as well.
"Through our interdisciplinary outpatient POC team, we can assess the specific needs of a clinic and provide insight into best practices to ensure quality of testing. In addition to immediate diagnostic capabilities of POC tests, understanding the impact of these tests on patient care in the various clinical settings can prevent potential patient safely issues," Arboleda and Garner wrote in the article.
The respiratory panel study, which was the subject of a presentation given by Garner at the Cambridge Healthtech Institute's Molecular Medicine Tri-Con Conference in San Francisco last month, sought to evaluate whether physicians would be less likely to prescribe antibiotics to patients with flu-like symptoms when using a highly sensitive rapid PCR flu test. The BioFire rapid PCR test flu test, FlimArray RP EZ, which tests for 11 viruses and three types of bacteria, has a sensitivity of more than 95 percent, meaning it is very unlikely to report a false negative, compared to rapid antigen tests which can range from 60 to 80 percent sensitive, Garner said.
Standardizing the use of a nucleic acid amplification-based PCR test required somewhat different training than is required for other types of point-of-care testing, such as antigen-based testing, Garner noted. While test interpretation was not an issue, as the machine interprets the test for the user, the high sensitivity of the test requires those performing the test to take extra precautions.
"The challenge with something like a sensitive molecular test for infectious disease is that if you are messy in your process, so let's say someone comes in with a cold, but they have a very high concentration of virus, if that gets spread around in the area where the testing is, you can see where there may be contamination that would then move to the next sample and you would have false positives," Garner said. "Because of that we had to be very careful in the training."
The respiratory panel study was conducted in just three urgent care clinics that have demonstrated particularly strong adherence to standardized protocols in point-of-care testing, he said.
While the team is still interpreting results, the data has shown that there are more factors to consider that affect whether or not antibiotics are prescribed than simply whether a virus is present or not, such as the age of the patient, and other underlying conditions may affect prescribing decisions. Eventually, ambulatory point-of-care test results may need to come with more detailed recommendations or best practices as to how test information should be used.
"This study isn't going to be big enough to make those recommendations, but it' is going to be large enough to reveal what set of questions we should be thinking about," Garner said.
While UCLA has not yet considered what other patient outcome studies might be conducted in the future, Garner said the team aims to continue to use the standardized ambulatory testing environment to further study patient outcomes in point-of-care testing. Future studies will likely depend on what other types of improved testing gets CLIA-waived, he noted.
"We are going to continue down this road," Garner said.